I'm having quite a big problem since yesterday with my Little Monster. It stopped in the middle of a print and since then the extruder temperature is locked between 500 and 515 celsius degrees while it's not heating.

I unmounted it and checked the thermistor on the extruder, it seems ok. And I noticed that even after unplugging the thermistor the extruder is still varying a bit (still between 500 and 515 degrees).

If anyone has an idea what's happening to my machine and what can I do ...